Method of making needled shoe stiffening material



A. W. CLOSSON, JR

Nov. 15, 1966 METHOD OF MAKING NEEDLED SHOE STIFFENING MATERIAL FiledFeb. 12, 1963 INVENTOR. ADDISON W. CLOSSON,JR.

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ATTORNEYS United States Patent 3,284,872 METHOD OF MAKING NEEDLED SHOESTIFFENING MATERIAL Addison W. Closson, Jr., Cambridge, Mass, assignorto Beckwith-Arden Inc., Watertown, Mass, a corporation of New HampshireFiled Feb. 12, 1963, Ser. No. 257,931 2 Claims. '(Cl. 28-722) Thisinvention comprises a new and improved sheet material for stiffening boxtoes and counters and includes within its scope box toe or counterblanks manufactured therefrom as well as a novel process of making thesame.

The invention is based on the discovery of the surprising and unexpectedadvantages realized from the employment for such uses of aresin-carrying textile fabric having on at least one surface a needlednap of synthetic resinous fiber of high tensile strength, such as rayon,acrylic or polyester fibers.

Heretofore box toe and counter stilfeners have included in theirstructure a woven or felted body impregnated or coated with athermoplastic or solvent-softening compound. When severely indented orbent such stiffeners have very generally broken down and shown fiberfracture. For this reason they have been, of course, deficient in thedesired spring back characteristic. On the contrary, the stiffener ofthis invention, comprising a fabric base combined with a needled nap ofrayon or the like is found to be practically unbreakable underconditions that would completely ruin a stiffener of previously knownstructure.

From this discovery flow many advantages. In the first place thestiffener responds to deflection with a high degree of spring back andso relieves the dealer or manufacturer of replacing shoes withpermanently damaged box toes.

In the second place satisfactory stiffeners of the needled type may bemanufactured in substantially thinner gauge than those of formerconstruction. The lasting operation is therefore facilitated and madeeasier and the style of the shoe correspondingly improved.

The cost of the needled type stiffener is substantially less than thatof stiifeners which have heretofore required a heavier more closelywoven base fabric. The napping operation to which it has been necessaryheretofore to subject cotton fabric impairs the tensile strength of thecotton and this step is also obviated by the present invention.

Moreover the present invention opens to the manufacturer a wide range ofpossible material in that the base fabric may be of any materialselected for its special field of use while the needled nap supplies thenecessary bibulous component for the stiffening compound and highstrength for the fabric. For example, the base fabric may be lightweight cotton woven or unwoven, fiberglass, metallic screening, felt,osnaburg, synthetic woven cloth, plastic film, paper, etc., while theneedled nap may be rayon or other synthetic or natural fiber.

Furthermore, the novel process which I employ in making my improvedstiffening material may be advantageously carried out in continuous orintermittent fashion at very moderate cost with machinery already available.

Other features and characteristics of the invention will be bestunderstood and appreciated from the following description of a preferredembodiment of the material, selected for purposes of illustration andshown, together with an outline of the process of manufacture, in theaccompanying drawing, in which:

FIG. 1 is a diagrammatic view suggesting the process and its relatedsteps,

3,284,872 Patented Nov. 15, 1966 FIG. 2 is a plan view of a box toeblank incorporating the invention, and

FIG. 3 is a sectional view on the line 3-3 of FIG. 2 and on an enlargedscale.

In further explanation of my invention it is noted that when a flannelcarries a nap, which it must do to absorb box toe latex resins, this napmust be obtained from the flannel by a scratching or napping processwhich weakens the flannel sheet, which, if carried to extremes, can leadto the formation of spots of very low tensile strength; while on theother hand, on the needled fabric, the nap is laid on from a carded battor web and then needled into a carrier sheet by a process that does notappreciably weaken the basic woven carrier. Therefore, much greater napscan be put on lighter pieces of woven carrier than in conventionalflannels and the lighter woven base will still, in many cases, be asstrong if not stronger than a scratch-napped flannel made from muchheavier sheeting. In other words, this napping process does not Weakenthe base carrier when the nap is applied by needling.

The web of napping which we apply to the woven base on the new needledfabric is normally made from a synthetic fiber such as rayon, nylon orDacron (du Pont trademark for polyester fiber) or combinations of thesesynthetic fibers, which in themselves as individual fibers can be mademuch longer and possess much greater tensile strength as individualfibers than do the short cotton fibers which are napped at random upfrom the cotton sheeting currently used in industrial fiannels-thepresent standard carrier for box toe manufacture. These fibers scratchedfrom the threads are apt to be of low grade cotton and have neither thelength nor the tensile to compare with the fiber which we are using asthe standard fill on the needled fabric.

Of course, the strength of the fibers which constitute the napping onthe surface of a box toe base carrier has nothing to do with its tensilestrength before the whole is saturated with resins but once this carrierhas been saturated or impregnated with a resin, the fibers then tend tobe locked together by the resin and they assume great importance inraising the tensile strength of the box toe material.

As shown in FIG. 1 the base fabric 10, which may be osnaburg or cottonscrim, is advanced as a continuous web through a conventional needlingmachine where it receives a carded batt 11 of staple nylon fibers uponits lower surface and a similar batt 12 upon its upper surface. Thecomponents thus assembled are passed beneath a bank of barbed needles 13by which the nylon fibers are drawn partly through the fabric 10 andpermanently united thereto.

The needled web is then advanced to a bath 14 of styrene latex andguided by a roll 15 beneath the surface thereof being thus completelysaturated and coated. Upon leaving the bath 14 the saturated needled Webpasses between squeeze rolls 16 by which excess latex is removed. Inplace of styrene latex I may employ other vinyl compounds, rubber latex,or solvent colloids or even thermosetting compounds in the form of hotmelt resins. In this connection it is important to note that the needledWeb will pick up a minimum of ten percent (10%) more saturant per squareyard than does napped cotton flannel of the same weight. The ratio ofbase fabric to resin saturant in the needled web averages 20:80, theimpregnant resin being as against about 70% which is about the best thancan be achieved when a napped flannel base is employed.

The tensile strength has a great deal to do with the breaking strength,or impact strength, of a box toe; as, for instance, after a polystyreneimpregnation of this new needled fabric and the subsequent activationand fusion of polystyrene resin by solvent, the polystyrene resin locksin place the fibers in the needled fill as Well as those of its basecarrier and I have obtained a much greater impact strength thancomparable box toe material made from regular cotton flannel would give.After activation, the same or higher impact strength is obtained, forinstance, in a given weight polystyrene box toe, even when using a lightcotton tobacco cloth carrier with a nap of these long, strong nylonfibers, as we get from the use of a very heavy cotton flannel whichcosts far more and which has much greater tensile strength in the rawunimpregnated state.

Of course, this greater impact strength may be increased even more byemploying a base carrier for the needled fill which has greater tensilein the raw state than the previously mentioned standard flannel. Thisstronger base for the fill, such as nylon, Dacron or glass-woven base oreven a very heavy cotton-woven base, on which to needle these longstaple artificial fibers, can give a much stronger tensile to the boxtoe carrier in the unimpregnated state.

After leaving the squeeze rolls 16 the saturated web is dried by beingpassed about heated drying cans 17-18. These may be located and spacedas desired and are merely conventionally represented in FIG. 1. Thedried web may now be immediately advanced to calender rolls 19-20 or itmay be coiled and calendered at any convenient later date. As a resultof the calendering operation the web is substantially compacted,hardened and reduced in thickness, to the desired gauge. Most mens shoemanufacturers employ box toe blanks within a range of .045 to .056" inthickness. The dried needled web may readily be reduced to suchthicknesses by calendering rolls 19-20. Where it is needed a heaviergauge box toe material acn be made with given weight of needled fabricthan with the same weight of cotton flannel. Conversely, the needledfabric may be held down to a lower gauge during manufacturing, if needbe.

Box toes made from this needled fabric are as easy, if not easier, toskive than conventional flannel base materials. The light and extensiblenature of the cotton scrim used as a carrier for the needled fabric in acured rubber box toe allows for much easier bedlasting, which is a verygreat advantage never before achieved with a cured rubber toe.

From the calendered sheet stock the required box toe blanks and counterlinings may be cut out. The box toe blank of FIGS. 2 and 3 is ofconventional shape, being .045 to .056" in thickness and having a widescarf formed by skiving along its rear edge. The sectional view of FIG.3 is enlarged about six diameters.

The following table indicates the superiority of box toes of needledmaterial above described compared with other box toes commerciallyavailable in the market at the present time.

AVERAGE RESULTS OF IMPACT TESTS Only experiments labeled l, 2 and 3 wereconducted with box toes of needled material and in respect to them therewas no actual cracking, only a slight hair-line checking. These threesamples could not be broken down and after the-tests recovery wasexcellent.

Tests marked Beckwith 47D and Beckwith 55D were conducted with box toesdrawn at random from the corn-v mercial stock of BeckWith-Arden Inc.Tests marked BX No. 40 Special, BX No. 37 and BX No. 50 Special wereconducted with box toes drawn at random from the commercial stock ofBixby Box Toe Co. Inc. All of these box toes were subjected todestructive testing while the box toes of experiments 1, 2 and 3successfully withstood the same testing treatment.

The fibers which are used for the napping, namely rayon or combinationof artificial fibers, are not only stronger in tensile, as I mentioned,but also have more elasticity and resiliency, which is a very importantpoint and therefore, when they are locked together by the styrene resinforming a hard shell, for instance, they are doubly protected against ahard blow or impact since they will not sever when extreme stress isapplied since they will give and return in a resilient and elasticmanner.

Since the manner in which the napping is applied to the needled fabricis not directionally warp and woof oriented but rather a mat wherefibers at random can absorb a load or stress which is applied anddistribute this load in all directions, I feel that this has anadvantage over the straight woven and conventionally-mapped flannelwhich is two directional only.

My invention may be embodied to good advantage in needled materialwherein the impregnate is a colloid soluble in a non-aqueous solution.Nitrocellulose, cellulose acetate or other cellulose derivatives orcombinations thereof may be employed and are readily absorbed by thecomposite Web as suggested in FIG. 1.

Having thus disclosed my invention and described in detail anillustrative embodiment thereof, I claim as new and desire to secure byLetters Patent:

1. The process of making stiffening material for box toes and counters,comprising the steps of needling a batt of staple rayon fibers to asheet of loosely woven osnaburg to form a bibulous ply of high tensilestrength, saturating the needled composite sheet in a bath ofpolystyrene latex, drying the saturated sheet, and thereby bonding therayon fibers together, and then compacting and severely compressing thedried sheet, thus forming a thin dry product carrying a charge ofpolystyrene amounting in weight to about of the weight of the wovenfabric base.

2. The process of making stiffening material of high tensile strengthfor shoe parts, comprising the steps of needling a batt of syntheticresin fiber to a thin textile sheet thereby forming a bibulous ply ofhigh strength, saturating the needled sheet in a bath of resinous latex,drying the saturated sheet thereby bonding the resin fibers together,and then calendering the dry sheet to a uniform thickness of 0.045 to0.056 inch carrying resinous latex amounting by weight to 80% of theweight of the textile sheet.

References Cited by the Examiner UNITED STATES PATENTS 1,825,827 10/1931 Smith 16l64 1,991,464 2/ 1935 Mellerio 161-85 2,059,132 10/1936McDermott 161-81 2,543,101 2/1951 Francis l6185 2,959,509 11/1960Marshall 161-81 X 2,970,365 2/1961 Morgenstern l56l48 X FOREIGN PATENTS888,146 l/ 1962 Great Britain.

EARL M. BERGERT, Primary Examiner.

L. T. PIRKEY, P. DIER, Assistant Examiners.

1. THE PROCESS OF MAKING STIFFENING MATERIAL FOR BOX TOES AND COUNTERS,COMPRISING THE STEPS OF NEEDLING A BATT OF STAPLE RAYON FIBERS TO ASHEET OF LOOSELY WOVEN OSNABURG TO FORM A BIBULOUS PLY OF HIGH TENSILESTRENGTH, SATURATING THE NEEDLED COMPOSITE SHEET IN A BATH OFPOLYSTYRENE LATEX, DRYING THE SATURATED SHEET, AND THEREBY BONDING THERAYON FIBERS TOGETHER, AND THEN COMPACTING AND SEVERELY COMPRESSING THEDRIED SHEET, THUS FORMING A THIN DRY PRODUCT CARRYING A CHARGE OFPOLYSTYRENE AMOUNTING IN WEIGHT TO ABOUT 80% OF THE WEIGHT OF THE WOVENFABRIC BASE.